GCMRC 2019 Annual Reporting Meeting Preview – Part 1 Adaptive Management Work Group Meeting March 6-7, 2019 Scott VanderKooi and Mike Moran U.S. Geological Survey Southwest Biological Science Center Grand Canyon Monitoring and Research Center U.S. Department of the Interior U.S. Geological Survey
Overview A bit on the fishy side More diversity in Mike’s talk tomorrow Emphasis on recent results and long-term trends HFE assessment – next week Bug flows update ( March 6, 2019 )
Humpback Chub ( March 6, 2019 )
( March 6, 2019 )
Spring Abundance of Adult Humpback Chub: Little Colorado River 2018 spring abundance estimate for sub-adults and adults similar to 2017. Adult abundance upward trend since 2015 continued. ( March 6, 2019 ) (Preliminary Data from VanHaverbeke et al. USFWS. 2018. Do Not Cite.)
Adult Humpback Chub Abundance (Adults ≥ 200mm TL in Little Colorado River aggregation ) Adult abundance as estimated in multi-state model is stable (or increasing slightly) and exceeds 2016 BiOp tier-1 trigger level of 9,000. Year Vertical lines represent 95% confidence intervals. (USGS Preliminary Data, 2019. Do Not Cite.) ( March 6, 2019 )
Spring Abundance of Sub-Adult Humpback Chub: Little Colorado River 2018 spring abundance estimate for sub-adult humpback chub (150-199 mm) in the Little Colorado River. 3-year average is 1,895 fish, exceeds 2016 BiOp tier-1 trigger level of 1,250. (Preliminary Data from VanHaverbeke et al. USFWS. 2018. Do Not Cite.) ( March 6, 2019 )
Fall Abundance of Sub-Adult Humpback Chub: Colorado River – JCM Reach Fall abundance estimates for sub-adult humpback chub (150-199 mm) in the mainstem Colorado R. near Little Colorado R. confluence. 3-year average exceeds 2016 BiOp tier-1 trigger level of 810. Year Vertical lines represent 95% confidence intervals. ( March 6, 2019 ) (USGS Preliminary Data, 2019. Do Not Cite.)
July Abundance of Age-0 Humpback Chub: Little Colorado River Although adult abundance is steady (or possibly increasing slightly), little age-0 production seen in the LCR for the past 3 years. If this continues, may see a decrease in adult abundance in the next 3-5 years. Year Vertical lines represent 95% confidence intervals. ( March 6, 2019 ) (USGS Preliminary Data, 2019. Do Not Cite.)
Apparent Survival Humpback Chub: Translocated vs Not Translocated Apparent Survival Assume if 300 fish are translocated yearly in perpetuity, adult abundance would be 350 adults higher vs. if no translocations occurred. (USGS and USFWS Preliminary Data, 2019. Do Not Cite.) ( March 6, 2019 )
NPS Tributary Native Fish Restoration: Bright Angel Creek and Havasu Creek Nonnative trout removals Humpback chub translocations Multiple monitoring metrics: abundance, survival, recruitment ( Slide courtesy Brian Healy, NPS ) ( March 6, 2019 )
Bright Angel Creek: Trends • Strong BNT year class in 2018: 2018 (red) adults likely due to ideal (low) flows during spawning/incubation • Very few adult BNT remaining • 2018 BNT abundance = 84% decline since 2012 (>90% in 2017) Weak year classes of native fishes • Bright Angel Creek: total, young-of-year, adult (likely due to drought) abundance 20000 18000 Abundacne Estimate - 2-pass data 16000 14000 12000 10000 8000 6000 4000 2000 0 2012 2013 2014 2015 2016 2017 2018 total >230 YOY (Slide courtesy Brian Healy, NPS. Preliminary data, do not cite) ( March 6, 2019 )
Bright Angel Creek: Trends, cont. Young trout flood vulnerability • Strong BNT year class in 2018: likely due to ideal (low) flows during spawning/incubation • Very few adult BNT remaining • 2018 BNT abundance = 84% decline since 2012 (>90% in 2017) Weak year classes of native fishes • Bright Angel Creek: total, young-of-year, adult (likely due to drought) abundance 20000 18000 Abundacne Estimate - 2-pass data 16000 14000 12000 10000 8000 6000 4000 2000 0 2012 2013 2014 2015 2016 2017 2018 total >230 YOY (Slide courtesy Brian Healy, NPS. Preliminary data, do not cite) ( March 6, 2019 )
Humpback c k chub translo locatio ions Havasu Creek: • Population estimate ~300 • Non-translocated/fish produced in situ catch continues to increase (~50% of abundance estimate in May, 2018) Apparent survival - all translocations Bright Angel Creek: 1 0.95 • May, 2018, Released 116 Monthly survival adult humpback chub 0.9 * (mean TL =257 mm) 0.85 0.8 • Preliminary apparent 0.75 survival ~80%; estimate will 0.7 change with additional data • Comparable to some Cohort or Shinumo Creek time period (time-varying model) *BAC - Preliminary estimate (Slide courtesy Brian Healy, NPS. Preliminary data, do not cite) ( March 6, 2019 )
Background image only - 2 ( March 6, 2019 )
Humpback C Chub C CPU PUE E by y year i in western Grand C Canyon Humpback chub CPUE in Mean Captures per Hoop Net Set (n) western canyon peaked Upstream in 2017. Despite a year over year decline, 2018 catches remained well above levels observed prior to recent increases. All size classes (juvenile Downstream to adult) were captured. Year (Preliminary Data from VanHaverbeke et al. USFWS. 2018. Do Not Cite.) ( March 6, 2019 )
Rainbow Trout and Brown Trout ( March 6, 2019 )
Background image only - 3 ( March 6, 2019 )
Rainbow Trout (≥ 175 mm FL) - Glen Canyon Rainbow trout catch increases seen in all size classes in 2018 likely due to high production and survival in recent years. (Preliminary data from Yard and Korman, 2018. Do Not Cite.) ( March 6, 2019 )
Rainbow Trout (all sizes) - Glen Canyon Catch Per Unit Effort (CPUE) 1,600 Rainbow trout catch peaks in the fall as young fish become susceptible to gear. 1,400 Catch drops over winter due to lower RBT CPUE (# fish / km) 1,200 survival rates of young fish. Observed year over year increases from 2015 – 1,000 2018 with a big jump in 2018. First look 800 in 2019 – similar to 2018. 600 400 200 0 Jan-2014 Apr-2014 Jul-2014 Sep-2014 Oct-2014 Dec-2014 Apr-2015 Jul-2015 Sep-2015 Oct2015 Dec-2015 Jan-2016 Apr-2016 Jul-2016 Sep-2016 Oct-2016 Jan-2017 Apr-2017 Jul-2017 Sep-2017 Oct-2017 Jan-2018 Apr-2018 Jun-2018 Sep-2018 Nov-2018 Feb-2019 SAMPLING PERIODS CPUE based on 1st Pass (Preliminary data from Yard and Korman, 2018. Do Not Cite.) ( March 6, 2019 )
Lees Ferry 1 gridline = 50 fish 5 mm bins Rainbow Trout length High levels of juvenile production frequency 2016-18. Recruitment into larger size classes becoming more histograms evident, especially in 2018. * * No Spring trip in 2018 (Preliminary Data from Rogowski et al. AGFD. 2019. Do Not Cite.) ( March 6, 2019 )
Lees Ferry Rainbow Trout angler CPUE Goal: CPUE ≥ 1 fish/ hr Angler catch rates are increasing in both the upriver boat fishery and the walk-in fishery. Boat fishery just below goal in AG&F management plan for Lees Ferry. Goal: Angler catch rate ≥ 1 Rainbow per hour (Preliminary Data from Rogowski et al. AGFD. 2019. Do Not Cite.) ( March 6, 2019 )
Rainbow Trout - Glen Canyon Relative Condition Factor (300 mm fish) Results from October Surveys Condition lowest in in Three Sample Reaches 2014, coincided with sharp decline in abundance. Values >1 since late 2015 provides indicator that fish in Glen Canyon are healthy. (Preliminary data from Yard and Korman, 2018. Do Not Cite.) ( March 6, 2019 )
Brown Trout CPUE 2 orders of magnitude less than rainbow trout Brown trout catch by AG&F flat from 2016 through 2018 and still comprise only a small proportion of fish in Glen Canyon. • 51 captured – Released 9 in TRGD reaches (5 tagged, 4 recaptures) – Removed 42 elsewhere (including 2 recaptures) (Preliminary Data from Rogowski et al. AGFD. 2019. Do Not Cite.) ( March 6, 2019 )
Stocked Triploid Rainbow Trout - Glen Canyon Release Recapture Location Locations AGFD released 526 triploid rainbow on Nov. 14, 2018 just upstream of Lees Ferry (RM 0). GCMRC recaptured 3 in Glen Canyon near - 4 mile on Feb. 10-11, 2019. No indication of substantive growth. No stocked fish were captured in upstream sample reaches. (USGS Preliminary Data, 2019. Do Not Cite.) ( March 6, 2019 )
Bug Flows ( March 6, 2019 )
What is a Bug flow? “Give bugs the weekends off” Weekend stable low flows from May-August Eggs laid on weekends never dry https://waterdata.usgs.gov/az/nwis/uv?site_no=09380000
Midge spatial catch pattern (prediction) Midge spatial pattern due to hydropower releases Bug Flows should minimize effect Troughs, particularly, should flatten (USGS Preliminary Data, 2019. Do Not Cite.) ( March 6, 2019 )
Midge spatial catch pattern (result) Spatial pattern evened out in 2018 Effect should be stronger if bug flows approved for 2019 (after a year of bug growth) 3 years of bug flows recommended by GCMRC to test hypothesis (USGS Preliminary Data, 2019. Do Not Cite.) ( March 6, 2019 )
Yearly light trap patterns • Midges stable • Caddisflies take off in 2018 • Caddisflies now approximate midge densities (USGS Preliminary Data, 2019. Do Not Cite.) ( March 6, 2019 )
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